class Fish{
    int weight;
}
class Lake{
    Fish fish;
    void setFish(Fish s){
        fish = s;
    }
    void eat(int n){
        fish.weight = fish.weight + n;
    }
}
class FishandLake{
    public static void main(String[] args) {
        Fish niqiu = new Fish();
        System.out.println(niqiu.weight);//初始重量
        Lake xihu = new Lake();
        Lake taihu  = new Lake();
        xihu.setFish(niqiu);
        taihu.setFish(niqiu);
        taihu.eat(15);
        System.out.println(niqiu.weight);//泥鳅重量
        System.out.println(xihu.fish.weight);//西湖重量
        System.out.println(taihu.fish.weight);//太湖重量
        xihu.eat(50);
        System.out.println(niqiu.weight);//泥鳅重量
        System.out.println(xihu.fish.weight);//西湖重量
        System.out.println(taihu.fish.weight);//太湖重量
    }
}